Keeping color in blue/purple acropora

[Phantom Phish]

I was in one of my LFSs recently, and they had a nice blue/purple acropora that I'm considering for my tank. My lighting is two 250 watt Iwasakis (6.5k), with three VHO actinics (each 36 inches/ 95 watts).

My question is, should I be able to keep the nice purple/blue color in this coral with the lighting I have? Would this coral likely keep its color better near the top of the tank, mid portion, or nearer the bottom? Tank is 24 inches to the sandbed, and lights are mounted about 10 inches above the water.

Appreciate any help.

[Phantom Phish]

OK, seems I was too simplistic in my question.

I've done some other searches, and found some information and articles written by Eric Borneman and Sanjay Joshi, that suggest that the color temperature of our light systems may have little to do with acroporas maintaining coloration, particularly the blues and purples that are so often sought after. Didn't realize this was such a controversial subject, but their contentions seem to be somewhat hotly debated by experienced hobbyists and their anecdotal evidence/experience of blue and purple acroporas turning brown under 6.5K lighting.

Maybe I should rephrase my question.

How many people who run Iwasaki lights (6.5K), have been able to keep the coloration of blue and purple acroporas? How about people running 10k and 20K lights?

[squid]

Did you see the Purple Caps on our site?

Those are/were under 250 Watt HQI 10K MH and 330 Watt VHO Super Actinic's. When I cherry picked them from the wholesalers, they almost looked brown under his light...65K, but when placed in our tank, they turned purple with hours.

Does that help?

[Geoff]

this is the problem i am having with my acros. they tend to turn brown under my 400w iwasakis. i am thinking i need to add more actinics to suppliment more to bring the K closer to 10k. Casey seems to think if i wait it out the colours will come back. so i am giving it a try. he uses iwasaki's on his tank. he has double the actinics i do though.

G~

[Phantom Phish]

Lise:
I just looked at the the purple M. capricornis on your website. Very pretty. Looks like they've all been sold already.

That seems to be what I've read from other hobbiests, that under 6.5 K lights many see a tendency for the blue and purple sps's to go brown, while others seem to be able to keep the colors under Iwasakis. But in the articles and postings I read from Borneman and Joshi, they seem to say color temperature of the lights is not what makes the coral keep or lose its color, but what you're feeding the corals (or what they're feeding on themselves) is what determines the coloration of the coral for the most part (although they admit they have no idea what you should feed the corals to keep or get that color). But my sense is that in the experience of most hobbiests, the majority see colorful corals go brown under lighting thats predominantly less than 10K.

So, I guess what I'm trying to get a handle on, is whether indeed that is the experience of most people who keep blue and purple sps's (that they have better luck with higher Kelvin lights), and if a significant percentage of people who have them under 6.5k lights have had them go brown. If the answer is that the majority of folks have had them go brown with Iwasakis, I guess I'd pass on getting this otherwise beautiful coral.

[Phantom Phish]

Geoff:
Thats interesting, how much actinic wattage do you and Casey have on your tanks?

[squid]

Phantom, here is a link from TRT archives addressing this very issue. You will find a lot of information on lighting and corals

http://www.thereeftank.com/forums/sh...threadid=20305

Hope this helps

[Geoff]

i do not know exactly what Casey has. he has just said that he uses 2 actinics for each of his iwasakis. so i am guessing he has 500w of iwasakis and 550w of actinics. please Casey let me know if i am wrong. this is on his 100g. this is just what i can figure out from all of his posts.

Rick has 500w of iwasakis and 220w of actinics on his tank he has good colour.

i have 800w of iwasakis and 330w of actinics. i am thinking of adding more.

hth,

G~

[squid]

I just looked at the the purple M. capricornis on your website. Very pretty. Looks like they've all been sold already

Thank you. Yes I sell those out pretty fast. But that's not the reason I sent you there. I just wanted you to see them under the 250 mh.

[cyberchef]

I'm running 500W 6500K Hamilton bulbs and 260W PC Actinic and have had no trouble keeping blues and purples in corals. When I was running all PC lighting (520W basically 50/50) and had no prob;lems then either. Actually I fel they had slightly more and deeper colors under the PC's than they do now.

I've had a few discusions with a couple of people and between us and a few others he has talked to, we feel that for growth use the 6500K Iwasakis but to color them up place them under PC or VHO with 50/50 or better/more Actinic.

I have a grow out frag tank with a 250W Iwasaki and 130W PC Actinic. This tank has only been setup for about 3 weeks (it's actually been setup for 6/8 mnonths but has only had lights for about 3 weeks) now but so far the corals areholding color and doing fine.

[squid]

Oh.. and please don't forget, water quality plays a BIG part in coral coloration and growth. IMO

[cyberchef]

Originally posted by squid
Oh.. and please don't forget, water quality plays a BIG part in coral coloration and growth. IMO

Good point Lise, I couldn't agree more. This is something a lot of us seem to take for granted and not mention. It's definately something tho, that needs to be mentioned.

[squid]

I got one right!!

[cyberchef]

Originally posted by squid
I got one right!!

LOL... Judging from the pics of the corals and such, I'd say you have a lot more than 1 right...

[Phantom Phish]

Thanks Lise and Cyberchef.

So maybe actinics are the answer?

Don, I'm pretty close to you in lighting set up with 500 watts total (two 250s) of 6.5k MHs and 285 total watts of actinic VHOs, so thats encouraging that you've had good luck with the purples and blues.